1．(2011·浙江高考)—How's your new babysitter?
—We________ ask for a better one. All our kids love her so much.
A. should
B. might
C. mustn't
D. couldn't
解析：句意：“你们的新保姆怎么样？”“我们不可能再请到更好的了。我们的孩子非常喜欢她。”“We couldn't ask for a better one.”中couldn't与better连用表示“不可能更好”。如I couldn't agree more.表示“我非常同意”。故选D项。
答案：D
